Deploy and Host Sim on Railway

Sim is an open source workspace for building, deploying and monitoring AI agents and workflows on a visual canvas. This template runs the complete upstream production stack, pinned to one release, with signup closed to everyone except the addresses you allow.

About Hosting Sim

Hosting Sim means running six services that share one database schema: the app, a realtime server, a migration runner, a scheduler, Postgres with pgvector and Redis. This template wires them together with private networking and generated secrets, and orders startup so the app waits for migrations.

What's Included

Sim: the Next.js app, API and workflow executor, with a volume for uploaded files
Realtime: the Socket.IO server behind collaborative editing, on its own domain
Migrations: applies the database schema, then signals the app that it is safe to start
Cron: the scheduler for scheduled workflows, polling triggers and connector syncs
Postgres: PostgreSQL 17 with pgvector for knowledge bases, on a volume
Redis: live chat and table events plus shared caches

Every secret is generated for you and shared between the services that need it.

Why this template

All three Sim images are pinned to the same release. They share one schema, and a floating tag breaks the stack on the next restart.
The app and Realtime wait for migrations to finish, so the first deploy does not race.
Redis and the scheduler are included. Without them live updates and scheduled workflows do not run.
Signup is restricted from the first minute.

First steps after deploy

Enter your email address in ALLOWED_LOGIN_EMAILS when you deploy. Only listed addresses can sign up or sign in.
Wait for all six services to turn green. The first boot runs every migration and can take several minutes.
Open the Sim domain and sign up with the address you allowed.
Add a model provider key in the workspace settings, or set OPENAI_API_KEY on the Sim service.
Build a workflow and run it.

Key environment variables

Variable	Service	Notes
`ALLOWED_LOGIN_EMAILS`	Sim	Required. Comma separated addresses allowed to register and log in.
`DISABLE_REGISTRATION`	Sim	Optional. Set to `true` once your accounts exist.
`ENCRYPTION_KEY`, `API_ENCRYPTION_KEY`	Sim	Generated. Back them up and never change them.
`NEXT_PUBLIC_APP_URL`, `BETTER_AUTH_URL`	Sim, Realtime	Update both services when you add a custom domain.
`NEXT_PUBLIC_SOCKET_URL`	Sim	Public address of Realtime.
`OPENAI_API_KEY`, `ANTHROPIC_API_KEY_1`	Sim	Optional provider keys for every workspace.

Common Use Cases

Build AI agents and multi step workflows on a visual canvas
Run scheduled or webhook triggered automations that call LLMs and tools
Give a team a shared, self-hosted workspace with knowledge bases on pgvector

Requirements

Use the Hobby plan or higher. Sim is a large application: upstream suggests 12 GiB of RAM in total for an evaluation install, and the app alone can use several gigabytes.

Upgrading

Back up Postgres, change the image tag on Migrations and wait for it to become healthy, then set the same tag on Sim and Realtime.

Dependencies for Sim Hosting

PostgreSQL with pgvector (included)
Redis (included)
An LLM provider key such as OpenAI or Anthropic (optional at boot, needed to run agents)
A mail provider such as Resend (optional, for invitations and password resets)

Deployment Dependencies

Why Deploy Sim on Railway?

Railway runs the whole stack in one project with private networking between services, generated secrets, volumes for the database and uploads, and one place to change image tags when you upgrade.